(2)Note. Selective or telemetering systems which may
be analogous to multiplexing techniques are not classified here
but elsewhere. (See References to Other Classes, below.)

(3)Note. The distinction between multiplexing and selective
or telemetry is: in multiplexing, the information
is unrestricted as to content, e.g., a
teletype-writer which uses an alphabet to transmit unlimited information, whereas
in selective or telemetry devices, the information is restricted
as to content, e.g., a transducer
measuring a single parameter.B. This class includes elements and circuits forming
subcombinations having a utility unique to multiplexing such as
rotary distributors used as multiplexers, synchronizers
used to control distribution of multiplexed channels, bridge
duplex circuits, resonant circuits having a special utility
in a frequency division multiplexing system.

(1)Note. Multiplex modulators, per se, are
not classified in this class. See classification elsewhere. (See
References to Other Classes, below.)

SECTION II - LINES WITH OTHER CLASSES AND WITHIN THIS CLASS

A. Electrical circuits which may be used in multiplexing systems
but are not unique to multiplex communications are classified in
the appropriate class for such circuits. (See
References to Other Classes, below.)

C Significantly claimed apparatus external to this class, claimed
in combination with apparatus under the class definition, which
perform multiplexing operations, are classified in the
class appropriate to the external device. (see
paragraph B above). (See References
to Other Classes, below for examples.)

D Nominally claimed apparatus external to this class in combination
with apparatus under the class definition, is classified
in this class unless provided for in the appropriate external class.
For example, a nominally recited coupled network which
includes significant multiplexing operations is classified herein.

E. Multiplexing systems and related devices found
in other classes, for which see below

Communications: Electrical,
subclasses 1.1 through 16.1for selective systems analogous to multiplexing
systems (including foreign art collection FOR 107 for a
selective loop system), subclass 853.1
for geophysical systems which may include multiplexing means, and subclasses
870.11-870.15 for telemetering which
may include multiplexing means.

Static Information Storage and Retrieval,
subclass 189.011and 230.01+, for a
static memory system with the handling of signal information or
the addressing of memory locations respectively analogous to multiplexing
techniques particularly subclasses 189.02 and 230.02
for such a system having multiplexed signals in each of the respective
systems.

Electrical Computers and Digital Processing Systems: Multiple
Computer or Process Coordinating, appropriate subclassesfor general purpose programmable computers which
may include multiplexing techniques wherein data is transferred
between the computers and processing of the data by the computers
occurs before or after the data transfer operation.

A relatively short distance data communication network linking
computers and other devices utilizing some type of standard control.

MULTIPLEXING

The simultaneous transmission of two or more information
signals in either or both directions over a common (same) transmission
medium in such a manner that the information signals may be discretely
recovered.

PROTOCOL

A specific set of rules about data format and data transmission
timing between two devices.

This subclass is indented under the class definition. Subject matter wherein an additional channel is derived
from two suitable arranged pairs of wires called side channels,
and each pair of wires is a channel itself and at the same time
acts as one conductor of the phantom channel.

(1)Note. The phantom channel is added by differentially modulating
the longitudinal, common mode signals of each wire channel at one
end of both wire channels and by detecting the difference at the other
end of said wire channels. Signals from the phantom channel thus
are canceled from the output of the individual wire channels, but
appear as the difference between values of common mode currents
carried by the wire channels.

This subclass is indented under the class definition. Subject matter wherein (a) a multiplexed channel is uniquely
identified and separated from other multiplexed channels by members of
a pair of mathematical functions having a sum of products or having
an integral that is zero or sometimes one under specified conditions,
or (b) particular mathematical processes are used to achieve multiplexing
techniques.

This subclass is indented under subclass 204. Subject matter wherein information is contained in the time
duration of a pulse (pulse width) and in the time of occurrence
(pulse position) of one pulse after a reference pulse.

This subclass is indented under subclass 206. Subject matter wherein supervisory information is transmitted
or received in a symbol pattern different from the symbol pattern
carrying the primary information, and wherein the symbol patterns
are generated using quadrature modulation technique (e.g., QAM,
QPSK, etc.).

This subclass is indented under subclass 203. Subject matter wherein two or more information signals,
each of the signals having a unique amplitude or level, are combined
to form a combined signal wherein the individual information signals
are separable by amplitude or level.

Error Detection/Correction And Fault Detection/Recovery, appropriate subclasses for fault detection and recovery
of a digital data system which is generic and not limited to multiplex communications,
particularly
subclasses 3+ for reconfiguration of a system to provide correction
in response to a fault.

This subclass is indented under subclass 225. Subject matter wherein the communication system has at least
one retransmission station wherein an alternate communication channel
is provided to convey information when a primary channel or link
is failed.

This subclass is indented under subclass 226. Subject matter wherein the multiplex repeater system has
a primary and a backup or protection line, and the backup line is
activated to route information data when the primary channel is
malfunctioning.

This subclass is indented under subclass 225. Subject matter wherein the multiplex system has a primary
and a backup line, and the backup is activated to routed
information data when the primary channel is malfunctioning.

This subclass is indented under subclass 229. Subject matter having means for regulating the amount of
data entering a multiplex network so as to prevent an overloading
or a further overloading of the network.

This subclass is indented under subclass 230. Subject matter wherein a signaling between an originating
terminal point and a destination terminal point regulates the amount
of information transmitted into the network.

This subclass is indented under subclass 236. Subject matter wherein fixed length packets which indicate
current network bandwidth (e.g., cell
rate) and congestion conditions are fed back to a network
source.

This subclass is indented under subclass 235. Subject matter wherein data is communicated on an alternate
channel when a preferred or desired channel is unavailable due to
excessive amounts of information already being carried on the preferred
or desired channel.

This subclass is indented under subclass 235. Subject matter wherein data is communicated on a channel
or channels based upon the determination that the selected channel
or channels will have the lowest (a) toll, expense, or (b) delay.

This subclass is indented under subclass 238. Subject matter wherein data is communicated in a network
utilizing fixed length asynchronous transfer mode packets (i.e., ATM
cells) based upon a determination that a selected channel
or channels will have the lowest toll or expense.

This subclass is indented under subclass 229. Subject matter having circuitry for disabling a device which
is transmitting more information than allocated or transmitting
for a greater period of time than allocated.

Error Detection/Correction and Fault Detection/Recovery,
subclasses 25+ for diagnostic testing of a generic information
processing system organization which is not limited to multiplex
communication, and subclasses 712+ for generic
transmission facility testing.

This subclass is indented under subclass 241. Subject matter wherein a link through a multiplex system
or a connection established through a multiplex switching network
is monitored for circuit continuity.

This subclass is indented under subclass 241. Subject matter wherein an equipment is tested by connecting
a received path to a transmitted path and monitoring the output
as an indication of the condition of the equipment.

(1)Note. Included are arrangements providing loopback
within a single terminal.

This subclass is indented under subclass 252. Subject matter wherein the communication parameter is the
amount of information transmitted per unit time over a network, and wherein
information signal is represented by one or a group of bytes preceded
by identification information indicative of a source or destination
station.

This subclass is indented under subclass 254. Subject matter wherein the network uses a set of rules for
solving a problem (configuration determination) in
a well defined number of steps and also has an ability to create
or adjust its own set of such rules.

This subclass is indented under subclass 255. Subject matter wherein one node from a plurality of nodes
in the network is selected as a root or base node with branches
interconnecting other nodes to the root node, and wherein
the network configuration is determined by the relationship between
the branch nodes and the root node.

This subclass is indented under subclass 254. Subject matter involving the configuration determination
in a network having a common transmission line (bus) forming
a communication path between a plurality of the user"s terminals
with the network.

(1)Note. Terminal address determination is properly
classified in this subclass.

This subclass is indented under the class definition. Subject matter for effectively transmitting messages simultaneously, one
in each direction, over the same transmission medium.

(1)Note. Circuits convertible to full duplex operation
are also classified here.

(2)Note. Full duplex describes two data paths which
allow simultaneous data transmission in both directions.
Half duplex describes one data path which allows data transmission
in either of two directions, but only one direction at
a time.

This subclass is indented under subclass 277. Subject matter having means at a station to reduce, neutralize, or
prevent transfer of an unwanted communication energy between a transmitter
and a receiver so that the transmitted communication energy (e.g., carrier
or message signal) does not adversely affect the receiver, or
so that the received communication energy does not adversely affect
the transmitter.

(1)Note. Means may be provided to feed a portion of
the transmission energy to the receiver, or a portion of
the received energy to the transmitter for monitoring or cancellation.

This subclass is indented under subclass 277. Subject matter including circuitry for compensating attenuation
losses of duplex signals or for increasing the communication range
for extension terminal equipment at either end of a duplex transmission
line.

This subclass is indented under subclass 277. Subject matter wherein duplex transmission and reception
signals access a transmission medium in separate time intervals
at such a rate as to give the appearance of a simultaneous transmission
and reception.

This subclass is indented under subclass 277. Subject matter wherein simultaneous transmission and reception
between communicating stations occur in separate portions of the
frequency spectrum of the transmission medium.

(1)Note. Classification here requires more than merely
two stations in communication on different frequencies. Full
duplex operation (i.e., simultaneous
transmission and reception by each station) is required.

This subclass is indented under subclass 276. Subject matter having means at a station to reduce, neutralize, or
prevent transfer of an unwanted communication energy between a transmitter
and a receiver so that the transmitted communication energy (e.g., carrier
or message signal) does not adversely affect the receiver, or
so that the received communication energy does not adversely affect
the transmitter.

(1)Note. Means may be provided to feed a portion of
the transmission energy to the receiver, or a portion of
the received energy to the transmitter for monitoring or cancellation.

This subclass is indented under subclass 282. Subject matter in which an electrical equivalent of a transmission
line is used to balance out an effect of local transmission current
on a local receiving device so the local receiving device responds
only to signals from the remote transmitter.

This subclass is indented under subclass 282. Subject matter wherein the duplex system comprises a circuit
type wheatstone-bridge in which substantial neutrality
of a receiving apparatus to transmitted currents is obtained by impedance
balance.

This subclass is indented under subclass 276. Subject matter including circuitry for compensating for
attenuation losses of duplex signals or for increasing the communication
range for extension terminal equipment at either end of a duplex
transmission line.

This subclass is indented under subclass 276. Subject matter wherein duplex transmission and reception
signals access a transmission medium in separate time intervals
at such a rate as to give the appearance of a simultaneous transmission
and reception.

This subclass is indented under subclass 276. Subject matter wherein simultaneous transmission and reception
between communicating stations occur in separate portions of the
frequency spectrum of the transmission medium.

(1)Note. Classification here requires more than merely
two stations in communication on different frequencies. "Full duplex
operation" (i.e., simultaneous transmission
and reception by each station) is required.

This subclass is indented under subclass 276. Subject matter wherein the transmission and reception of
signals occur alternately rather than substantially simultaneously, but
where the circuitry is convertible to full duplex operation.

This subclass is indented under the class definition. Subject matter wherein the multiplex feature is unique to
a system in which data flow is normally slow and data is not recurring
at exactly the same periods.

(1)Note. Examples of such systems are teletypewriter
and telegraphy.

(2)Note. A signal transmission speed lower than 300
symbols per second may be considered a low speed transmission in the
scope of this class.

This subclass is indented under subclass 298. Subject matter in which a representation of the time elapsed
between a previous scan and a data transition from one logic state
to another is transmitted along with information about the logic
value of the data either before or after the transition.

This subclass is indented under subclass 298. Subject matter having a signal supply means which rotates
for successively connecting lines, stations, instruments (e.g., a
sunflower), or having switches which are selectively
controlled by a code selection mechanism (e.g., keyboard).

Machine Element or Mechanism,
subclass 395for a system for synchronizing the rotary motion
of a plurality of shafts where adjustable gearing is utilized to
control the rotation of at least one of the shafts.

Electrical Transmission or Interconnection Systems,
subclasses 82, 83, and 87 for an electrical
system having a plurality of supply circuits or sources of supply
with means for controlling the connection or disconnection of the
supply circuits or sources by means responsive to the frequency and/or
phase relationship between the circuits or sources (the
control may involve the control of the speed or angular relation
of a generator or converter with respect to another; see subclass
82 where plural rotary converters are involved and subclass 84 where
plural generators are involved); and subclass
123 for miscellaneous electrical switching systems where the switching
operation is controlled by the differential speed between two bodies.

Electricity: Motive Power Systems,
subclasses 41+ for plural electric motor systems having electrical
synchronizing interconnection for maintaining synchronization between
the motors; subclasses 68+ for plural electric
motor systems with means for controlling the running speed of one motor
relative to the speed of another motor including such systems for maintaining
the motors in synchronism; and subclass 85 for the miscellaneous
plural electric motor systems with synchronizing or phasing control for
the motors.

Communications: Electrical,
subclasses 870.11+ for a telemetering system having a rotary distributor; subclass
681 for electric alarm which indicate the synchronism or lack of synchronism
of a plurality of shafts; and subclass 318 for a miscellaneous signaling
system having synchronized distributors at the transmitter and receiver.

Horology: Time Measuring Systems or
Devices,
subclasses 46+ for clock systems which include a master clock and
a secondary or receiving clock where the clocks are electrically
controlled or operated; subclasses 52+ for the
master clock of such a system with its electrical circuits and connections; and
subclasses 59+ for the secondary or receiving clock of
such a system with their immediate operating mechanism.

This subclass is indented under the class definition. Subject matter in which conversion from one multiplex technique
to a different multiplex technique is performed (e.g., conversion between
time division multiplex and frequency division multiplex).

This subclass is indented under the class definition. Subject matter wherein a transfer of information samples
is achieved by closing access switches to a common bus for a predetermined
portion of a cycle of a resonant frequency determined by reactive
components associated with each subscriber line.

This subclass is indented under the class definition. Subject matter utilizing techniques that strictly speaking
do not utilize resonant transfer but are closely analogous to and
are designed as replacements for resonant transfer techniques.

This subclass is indented under subclass 310.1. Subject matter wherein plural nonmobile base stations
provide service to different geographical areas having their boundaries
touch each other on a line or a point.

through 338,for generic plural contiguous regions served by
respective fixed stations, and subclasses 331-334 for
hand-off control in generic plural contiguous regions served
by respective fixed stations.

This subclass is indented under subclass 310. Subject matter wherein a direction for delivery accompanying
message information are transmitted to or received by more than
one corresponding remote station or group of remote stations.

This subclass is indented under subclass 313. Subject matter in which access to the transmission medium
is divided into discrete time intervals, and information
from respective channels is transmitted in different time intervals.

This subclass is indented under subclass 310. Subject matter having at least a station which retransmits
signals of other stations to compensate for attenuation losses or
to extend the communication range between a group of stations.

This subclass is indented under subclass 316. Subject matter having a scheme for reaching a communication
medium in which a station is assigned a channel in response to that
station"s request for access and the assignment lasting until it
is withdrawn.

This subclass is indented under subclass 319. Subject matter wherein spread spectrum codes are allocated
to allow multiple signals occupying the same channel bandwidth to
be transmitted simultaneously without interfering with one another.

This subclass is indented under subclass 319. Subject matter in which a station is assigned a vacant time
slot channel in a time multiplex frame in response to that station"s
request for access and the assignment lasting until it is withdrawn.

This subclass is indented under subclass 321. Subject matter wherein the airborne or satellite repeater
has an apparatus for rearranging the order of the received time
slots, comprising a plurality of receiving and transmitting
antennas which cover different geographical regions, and
wherein received information can be routed to the appropriate transmitting
antenna.

This subclass is indented under subclass 321. Subject matter including means for insuring that the transmission
and reception of time channel multiple access information has a proper
time relationship.

This subclass is indented under subclass 319. Subject matter wherein the airborne or satellite repeater
has a plurality of receiving and transmitting antennas which cover
different geographical regions, and wherein received information
can be routed to the appropriate transmitting antenna.

This subclass is indented under subclass 316. Subject matter wherein information signals are communicated
between stations by assembling or separating the signals via different
time periods on a common transmission medium.

This subclass is indented under subclass 315. Subject matter wherein the repeater is used in a system
having two or more stations communicate using one channel of a plurality
of channels; the channel is assigned based upon the availability
of the plurality of channels, and the assignment is controlled
by sending supervisory information over a control channel.

(1)Note. The channel assignment for a communication
may vary during the communication between the two stations.

(2)Note. The assignment of a channel bearing supervisory
information may vary with time, generally daily.

This subclass is indented under subclass 310. Subject matter wherein plural nonmobile base stations provide
service to different geographical areas having their boundary touching
each other on a line or a point, and wherein communications
between mobile units navigating in and out of the areas are regulated
by the nonmobile base stations.

Telecommunications,
subclasses 450+ , 464, and 509+ for channel
allocation in a cellular radiotelephone system, a private
cordless telephone, and radio telecommunications system in
general, respectively.

This subclass is indented under subclass 331. Subject matter using a process or apparatus which measures
a selected signal characteristic which will serve as a basis for
making a determination whether or not to hand-off the mobile station.

This subclass is indented under subclass 332. Subject matter wherein the selected signal characteristic
is measured by determining a ratio of erroneous bits to the total
number of bits communicated at a given time period.

This subclass is indented under subclass 332. Subject wherein a station (usually a base station) uses
a plurality of directional antennas for transmitting or receiving
information, and wherein signals from another station (usually mobile) are
received by two or more of the antennas and the hand-off
is performed based upon signal quality measurements received on the
two or more antennas.

This subclass is indented under subclass 329. Subject matter wherein spread spectrum codes are allocated
to allow multiple signals occupying the same channel bandwidth to
be transmitted simultaneously without interfering with one another.

This subclass is indented under subclass 329. Subject matter wherein information signals are communicated
between stations by assembling or separating the signals via different
time periods on a common transmission medium.

This subclass is indented under subclass 336. Subject matter having a scheme for reaching a communication
medium in which a station is assigned a vacant time slot channel
in a time multiplex frame in response to that station"s request
for access and the assignment lasting until it is withdrawn.

This subclass is indented under subclass 328. Subject matter wherein the base stations in the geographical
area communication system are interconnect by a common communication
bus, that allows wireless communication devices to communicate
with other wireless communication devices or wired communication
devices.

This subclass is indented under subclass 310. Subject matter wherein two or more stations communicate
using one channel of a plurality of channels; the channel
is assigned based upon the availability of the plurality of channels, and the
assignment is controlled by sending supervisory information over
a control channel.

(1)Note. The channel assignment for a communication
may vary during the communication between the two stations.

(2)Note. The assignment of a channel bearing supervisory
information may vary with time, generally daily.

This subclass is indented under subclass 310. Subject matter wherein spread spectrum coding techniques
allow multiple signals occupying the same channel bandwidth to
be transmitted simultaneously without interfering with one another.

This subclass is indented under subclass 310. Subject matter wherein information signals are communicated
between stations by assembling or separating the signals via different
frequency bands of a common transmission medium.

This subclass is indented under subclass 343. Subject matter having a scheme for reaching a comunication
medium in which a station is assigned a frequency channel in response
to that station"s request for access and the assignment lasting
until it is withdrawn.

This subclass is indented under subclass 310. Subject matter wherein information signals are communicated
between stations by assembling or separating the signals via different
time periods on a common transmission medium.

This subclass is indented under subclass 345. Subject matter having a scheme for reaching a communication
medium in which a station is assigned a vacant time slot channel
in a time multiplex frame in response to that station"s request
for access and the assignment lasting until it is withdrawn.

This subclass is indented under subclass 351. Subject matter wherein the switching network has both (a) a
switch which establishes a path between a source and destination
with the path being held for the duration of the communication, and (b) a
switch which routes information based on an address associated with
the information data in a channel which is only occupied for a duration
of the time required to transmit the information data and the associated
address.

This subclass is indented under subclass 351. Subject matter wherein the switching network establishes
a path or channel between two or more terminals and permits the
exclusive use of the connection between them until the connection
is released.

(1)Note. A switching exchange or a concentrator with
multiplex signals are placed in ths subclass.

(2)Note. The distinction between multiplexing and selective
or telemetry devices is: in multiplexing, the
information is unrestricted as to content, e.g., a teletypewriter
which uses an alphabet to transmit unlimited information, whereas in
selective or telemetry devices, the information is restricted
as to content, e.g., a transducer
measuring a single parameter.

Telephonic Communications, appropriate subclasses relating to a telephonic device, particularly
subclass 290for multiplexed switches and subclasses 242+ for
a switch having nonmultiplexed signals to be switched, and
subclass 333 for a concentrator.

This subclass is indented under subclass 357. Subject matter including procedures, techniques, or
apparatus to implement a supervisory function necessary for a proper
switching of information from an input of the switching network
to an output of the network.

This subclass is indented under subclass 360. Subject matter in which an equivalent N-stage switch
is achieved with less than N-stage by "folding" back the
output of one stage to connect with the input of a preceding stage.

This subclass is indented under subclass 360. Subject matter in which time switching occurs by connecting
communication lines to a common line (bus) for
a time sufficient to transfer information between the lines (e.g., one
time slot).

Electrical Computers and Digital Data Processing
Systems: Input/Output,
subclasses 1+ for transferring data from one or more peripherals
to one or more computers or digital data processing systems for
the latter to process, store, or further transfer
or for transferring data from the computers or digital data processing
systems to the peripheral.of information processing system.

This subclass is indented under subclass 362. Subject matter which includes a particular method, apparatus, or
technique dealing with the storage of supervisory or control information
for controlling the switching.

This subclass is indented under subclass 360. Subject matter wherein information in a sequential transmission
format is changed to a multipath parallel transmission format, or
vice versa, at an entrance or exit of the switching system.

This subclass is indented under subclass 366. Subject matter which includes a particular method, apparatus, or
technique dealing with the storage of supervisory or control information
for controlling the switching.

This subclass is indented under subclass 360. Subject matter in which the switching system is organized
to have (a) a time stage which reorganizes the
order of time slots and (b) a space stage which
switches time slots on incoming lines to a desired outgoing line
in either order.

This subclass is indented under subclass 369. Subject matter having a space switch or switches which are
not the first or last stages of a circuit switching network (i.e., time-space plus
an additional switching stage).

This subclass is indented under subclass 370. Subject matter which includes a particular method, apparatus, or
technique dealing with the storage of supervisory or control information
for controlling the switching.

This subclass is indented under subclass 369. Subject matter which includes a particular method, apparatus, or
technique dealing with the storage of supervisory or control information
for controlling the switching.

This subclass is indented under subclass 360. Subject matter in which information in time slots of incoming
lines is switched to desired destinations only by storing or delaying
the information until the desired instant of readout.

This subclass is indented under subclass 375. Subject matter which includes a particular method, apparatus, or
technique dealing with the storage of supervisory or control information
for controlling the switching.

This subclass is indented under subclass 378. Subject matter wherein a particular storage control apparatus
or technique is utilized to control the writing of incoming data
information into a storage device and the reading of data information
therefrom for transmission.

This subclass is indented under subclass 360. Subject matter wherein the switching control is for a switching
system that has a plurality of inputs and a plurality of outputs
wherein any input can be connected to any output for spatially displacing
the information.

This subclass is indented under subclass 360. Subject matter which includes a particular method, apparatus, or
technique dealing with the storage of supervisory or control information
for controlling the switching.

This subclass is indented under subclass 381. Subject matter wherein a particular storage control apparatus
or technique is utilized to control the writing of incoming data
information into a storage device and the reading of data information
therefrom for transmission.

This subclass is indented under subclass 381. Subject matter wherein a particular apparatus or technique
is utilized to control the reading or writing of control information
from or to a control memory.

This subclass is indented under subclass 384. Subject matter wherein a communication system distinct from
the switching system is provided for the communication of signaling information (i.e. CCITT
Signaling System No. 7).

This subclass is indented under subclass 351. Subject matter wherein information data to be switched is
organized with one or more bytes preceded by an identification information indicative
of a source or destination station.

(1)Note. The switching of the message having an address
header is commonly called packet switching.

This subclass is indented under subclass 392. Subject matter wherein information concerning the address
of nodes or switches in the route of a packet are serially linked
together in the packet to provide information for the route of packets.

(1)Note. For example, the packet is transmitted
through a plurality of nodes, and the address of all the
nodes in the route will be added to the address field of a packet.

This subclass is indented under subclass 389. Subject matter wherein a rearrangement of packets order
is performed before being outputted to ensure that the packets are
outputted in the same order as the packets received by the network.

Telecommunications,
subclasses 422.1 through 460for a zoned or cellular telephone system, subclasses 436-444
for hand-off in a zoned or cellular telephone system, subclass 445
for call routing in a zoned or cellular telephone system, subclass
455 for channel seizing in a zoned or cellular telephone system.

through 395.65,for adapting details, subclass 395.65
for adapting details of connectionless protocols such as IP or
UDP into fixed length packets, subclasses 465-473
for adaptive communication techniques including conversion between
protocols in general, and subclass 474 for assembly or disassembly
of messages having address headers.

This subclass is indented under subclass 395.6. Subject matter wherein data having an unchanging bit rate
is formatted/mapped into fixed length packets or vice versa.

(1)Note. Typically, this involves AAL1 format.

(2)Note. Included here are details of adapting connection-oriented, constant
bit rate (CBR) or isochronous data, for
example, voice data which is transferred on ISDN (Integrated
Services Digital Network) lines or details of using AAL1.

through 395.54,for a multiprotocol network, subclass
395.52 for a multiprotocol network involving IP over a fixed
length packet network, subclass 395.53 for a multiprotocol
network which is an emulated LAN, and subclass 395.64
for adapting connection oriented VBR data into fixed length packets.

This subclass is indented under subclass 395. Subject matter wherein the routing of a message from a source
to a destination is performed by a plurality of nodes which share
the control of switching and routing functions of the network.

This subclass is indented under subclass 396. Subject matter wherein packets of information are communicated
between two or more stations on physical paths or circuits which
may vary with time during a connection, and are identified
using a transparent addressing scheme.

(1)Note. The time varying paths or circuits are also
called virtual paths (VP) or virtual circuits (VC).

This subclass is indented under subclass 398. Subject matter wherein packets of information are communicated
between two or more stations on physical paths or circuits which
may vary with time during a connection, and are identified
using a transparent addressing scheme.

This subclass is indented under subclass 389. Subject matter having a switching architecture in which
a plurality of switch nodes are provided such that the switching
function is spread out over a geos:graphical area.

This subclass is indented under subclass 401. Subject matter wherein networks interconnected by the bridge
are characterized by having a common transmission line with a plurality
of terminals connected thereto.

This subclass is indented under subclass 400. Subject matter having interconnection between plural couplers
that distributes signal from one or more transmission line input
among a larger number of output lines.

This subclass is indented under subclass 400. Subject matter wherein packets of information are communicated
between two or more stations on physical paths which are varying
with time during a connection, and are identified using
a transparent addressing scheme.

This subclass is indented under subclass 389. Subject matter wherein pathfinding through a packet switch
involves a particular buffer processing arrangement for control
of communication of packets in a packet network.

This subclass is indented under subclass 420. Subject matter wherein the terminals to be connected to
a transmission line network by an interface are interconnected to
the interface by a common transmission line.

This subclass is indented under subclass 422. Subject matter wherein a data distribution system containing
a central node or hub connected to one end of each of three or more
branches and each other end of the branches is connected to a member
of a local area network multiplex system, and all routing
of network data takes place through the central node.

This subclass is indented under subclass 389. Subject matter wherein messages are transferred from inputs
to outputs of a switch node by temporarily providing a physical
path between the inputs and outputs in order to route the messages.

This subclass is indented under subclass 351. Subject matter including facilities which permit (a) a
storage of all or part of a message when no outgoing link to a destination
is free and (b) a subsequent transmission to the
destination when such a link becomes free.

This subclass is indented under subclass 351. Subject matter wherein signals to be switched are frequency
division multiplexed in the transmission medium having a frequency
spectrum divided into segments and respective information channels
are transmitted in different segments.

This subclass is indented under subclass 431. Subject matter wherein a direction for delivery accompanying
message information are transmitted to or received by more than
one corresponding remote station or group of remote stations.

This subclass is indented under subclass 431. Subject matter wherein the system adapts to changing traffic
conditions by sending only data from active channels and by suppressing data
from inactive channels.

This subclass is indented under subclass 433. Subject matter in which a switching device is used to reduce
the number of transmission channels required to serve remote stations
by allocating a transmission channel to a remote station only when
the remote station requests service (e.g., by
going off hook).

This subclass is indented under subclass 434. Subject matter including telephone switching equipment whereby
a user"s line is connected to an idle line when he starts talking
and is disconnected when he stops talking.

This subclass is indented under subclass 431. Subject matter wherein the assignment of a channel is controlled
by a supervisory signal communicated on a line which is distinct
from the line used for communicating information signals.

This subclass is indented under subclass 439. Subject matter wherein a first bus carries information in
time slots and a second bus carries time slot reservation and request
signal for controlling access of information in the time slot of the
first bus.

This subclass is indented under subclass 431. Subject matter wherein spread spectrum coding techniques
allow multiple signals occupying the same channel bandwidth to
be transmitted simultaneously without interfering with one another.

This subclass is indented under subclass 431. Subject matter having a scheme for reaching a communication
medium in which a station is assigned a vacant time slot channel
in response to that station"s request for access and the assignment
lasting until it is withdrawn.

This subclass is indented under subclass 431. Subject matter having a reservation scheme for reaching
a communication medium in which a station is assigned a carrier; the
idle state of a communication channel is determined by sensing the
presence or absence of a carrier signal on the channel.

(1)Note. CSMA with collision detection (CSMA/CD) or
a listen while talk scheme (LWT) is the basis
of the Ethernet protocol. In this scheme, a user
listens to a channel while sending out a message and immediately
ceases transmission before it is completed when a collision with
another simultaneous transmitting user is detected.

This subclass is indented under subclass 445. Subject matter wherein an order of importance is assigned
to stations or information to resolve situations in which plural
stations attempt to gain access to the same communication channel
at the same time.

This subclass is indented under subclass 447. Subject matter wherein after a data collision is detected, the
stations which caused the collision vary the amount of time before
an attempt to transmit again according to a priority scheme.

This subclass is indented under subclass 449. Subject matter in which a signal indicative of an occupancy
or nonoccupancy state of a communication channel is sent to control
access to the communication channel.

(1)Note. The signal identifying the idle or busy state
of a channel is also called the token.

This subclass is indented under subclass 452. Subject matter wherein more than one idle or busy signal
is present on the loop or ring since multiple frames of information
which contain the signals are present on the loop or ring at the same
time.

This subclass is indented under subclass 452. Subject matter wherein an order of importance is assigned
to stations or information to resolve situations in which plural
stations attempt to gain access to the same communication channel
at the same time.

This subclass is indented under subclass 458. Subject matter including techniques or apparatus to resolve
the right of a terminal to use a time slot channel when two or more
terminals desire to use the channel simultaneously.

This subclass is indented under subclass 431. Subject matter including techniques or apparatus to resolve
the right of a terminal to use a common communication channel when
two or more terminals desire to use the channel simultaneously.

This subclass is indented under the class definition. Subject matter including details of methods or apparatus
for formatting, converting, combining, or
distributing information signals for transmission or reception via
more than one time or frequency channel.

This subclass is indented under subclass 464. Subject matter in which the transmission format changes
or adapts automatically, or is programmed for changing
traffic requirements, or accommodates a plurality of sources
having diverse characteristics, (e.g., rates
or data format).

This subclass is indented under subclass 466. Subject matter including means for converting format and
timing of control or supervisory information exchanges between two
systems governed by different set of communicating rules.

This subclass is indented under subclass 465. Subject matter including adaptive processing of information
which is compliant with rules as set forth in a tiered (layered) structured
communication.

(1)Note. An example of a multiple layer network is
the Open System Interconnection (OSI) Reference
Model which comprises seven layers respectively named:
Physical, Data Link, Network, Transport, Session, Presentation
and Application. Each layer assumes an independent function
which could be individually modified without destabilizing the entire
system protocols.

This subclass is indented under subclass 464. Subject matter including (a) a process
of combining into a collective unit plural messages having each
an address header, or (b) a process of
decombining a collective unit of messages.

This subclass is indented under subclass 464. Subject matter in which each multiplexed channel consists
of a unique code word which carries the information.

(1)Note. Separation of each multiplexed channel is usually
achieved by correlation detection.

(2)Note. PCM or pulse code modulation, which
is a particular technique for transmitting digital signal, should
not be classified in this subclass if its use is not to make a channel
distinct in multiplex communications.

(3)Note. A synchronizing word which may use a particular
coding sequence for synchronization purpose is classified in subclasses
503+.

This subclass is indented under subclass 464. Subject matter wherein information signals are communicated
between stations by assembling or separating the signals via different
frequency bands on a common transmission medium.

This subclass is indented under subclass 480. Subject matter wherein a group of signals occupying a definite
frequency band is transferred from one position in the frequency
spectrum to another in such a way that the arithmetic frequency
difference of signals within the band is unaltered.

This subclass is indented under subclass 480. Subject matter including features specific to a generation
of a basic frequency wave (carrier wave); such
basic wave is modulated by an information bearing signal (modulating
signal) in a modulation process.

This subclass is indented under subclass 480. Subject matter in which a frequency multiplex composite
spectrum is produced or resolved into its constituent channels by
digital processing techniques (e.g., digital
filters).

Communications: Electrical,
subclasses 12.32 through 12.39for remote control over power line, subclasses
538-538.17 for signaling over power line, and
subclasses 870.18-870.24 for a telemetric
carrier signaling system.

Telecommunications,
subclasses 400+ for a super audible telephone carrier system where
a super audible carrier wave for transmission of telephone signals
is transmitted over an electrical system other than a baseband telephone
line.

This subclass is indented under subclass 480. Subject matter in which information is transferred over
one or more common frequency channel shared by a plurality of stations
having the same level of control.

This subclass is indented under subclass 480. Subject matter having a retransmitting station between communicating
stations to compensate for transmission attenuation losses or to extend
the range of communication between a group of stations.

This subclass is indented under subclass 480. Subject matter including means for transmitting supervisory
or indicating information ancillary to principal information being
transmitted (e.g., E and M signaling).

This subclass is indented under subclass 464. Subject matter wherein information signals are communicated
between stations by assembling or separating the signals via different
time periods on a common transmission medium.

This subclass is indented under subclass 498. Subject matter including a signal (pilot) separable from
the usual information transmitted, which signal is utilized for
control, maintenance, or improvement of signal quality.

This subclass is indented under subclass 498. Subject matter having a retransmitting station between communicating
stations to compensate for transmission attenuation losses or to extend
the range of communication between a group of stations.

This subclass is indented under subclass 498. Subject matter including a means for insuring that the transmission
and reception of time multiplex information has a proper time relationship.

(1)Note. Included herein is a phase locked loop synchronizer
unique to multiplex and a system analogous to pulse stuffing or
deletion which utilize a guard interval but do not stuff or delete,
but rather adjust timing to prevent conflict.

This subclass is indented under subclass 503. Subject matter in which synchronization is achieved by identifying
the absence of data transmission for a predetermined interval (i.e., a
gap) and using that absence to identify a reference point within
a transmission interval.

This subclass is indented under subclass 503. Subject matter wherein synchronization of a pulse train
is achieved by (a) inserting extra pulses into the train when pulses
arrive too slow or (b) removing pulses from the train when pulses
arrive too fast.

This subclass is indented under subclass 505. Subject matter wherein a course of action is taken if a
receiver station ignores a block of data because an error has occurred
or the receiver possesses no more buffer space.

This subclass is indented under subclass 503. Subject matter wherein the clock frequency adjustment of
one station is based upon information about the status of clock
signals originating at other stations of the system.

This subclass is indented under subclass 507. Subject matter including means to adjust the time at which
a station transmits information into an assigned time period in
order to compensate for transmission delays which are related to
the length and type of communication media.

This subclass is indented under subclass 503. Subject matter in which the synchronization is performed
on a cycle of a recurring number of data bits (frame) rather than
on the individual channels or bits in the frame.

This subclass is indented under subclass 509. Subject matter wherein the information used for synchronizing
the information stream is placed in multiple time locations within
a time period defining more than one frame.

This subclass is indented under subclass 510. Subject matter wherein plural identical synchronizing words
are transmitted so that the words may be compared to ensure the
proper recognition of the synchronizing words.

This subclass is indented under subclass 509. Subject matter wherein the information used for synchronizing
the information stream is placed in multiple time locations within
the time period defining the frame.

This subclass is indented under subclass 512. Subject matter wherein the information used to synchronize
the information stream consists of a multiplicity of multibit words
which are distributed in the frame.

This subclass is indented under subclass 509. Subject matter wherein a particular sequence of bits is
utilized to ensure the proper recognition of the synchronizing information
so that the information may be properly decoded.

This subclass is indented under subclass 517. Subject matter wherein multiple versions of a clock signal
are provided, and wherein each of the clock signals are phase shifted
in relation to each other.

This subclass is indented under subclass 503. Subject matter in which a synchronization bit has a width,
amplitude, phase, or other property which serves to distinguish
the synchronization bit from data bits.

This subclass is indented under subclass 498. Subject matter where (a) information is read out at a faster
rate than it is stored, resulting in a time compression, or conversely
(b) where it is stored at a faster rate than it is read out, resulting
in a time expansion.

This subclass is indented under subclass 498. Subject matter having means for transmitting or detecting
signaling information ancillary to the principal information transmitted
by the system (e.g., dial pulse, onhook/offhook, and ringing
information all ancillary to the information conveyed by a telephone
call).

This subclass is indented under subclass 522. Subject matter wherein a bit which is normally used to convey
main information is temporarily used for supervisory information.
(e.g., the 8th bit of a byte of information is temporarily used for
signaling).

This subclass is indented under subclass 522. Subject matter in which gaps in the principal information
transmitted are used for the transmission of ancillary data (e.g.,
signaling data transmitted during gaps in a speech signal).

This subclass is indented under subclass 498. Subject matter directed to (a) a scanning or sampling switch
(multiplexer) operating above the Nyquist rate, or to (b) a demultiplexer
or desampling switch (distributor) so operating, and including a
means for improving the accuracy of sampled data, especially for
a low level signal.

This subclass is indented under subclass 498. Subject matter directed to (a) a scanning or sampling switch
(multiplexer) operating above the Nyquist rate, or to (b) a demultiplexer
or desampling switch (distributor) so operating, and in which the
signals respectively from or to the multiplexer or distributor are
transmitting in pulse amplitude modulated format (PAM).

This subclass is indented under subclass 498. Subject matter directed to (a) a scanning or sampling switch
(multiplexer) operating above the Nyquist rate, or to (b) a demultiplexer
or desampling switch (distributor) so operating, and utilizing an
electron beam switching device such as a cathode-ray tube with target electrode
for multiplexing or distribution.

This subclass is indented under subclass 498. Subject matter wherein the multiplex system has only one
input and one output and the amount of information transmitted per
unit time is different at the input and the output

Art collection of the multiplex communication system consisting
of multiple communication systems interconnected to form a larger
communication system encompassing a larger area than that provided
by any one of the interconnected communication systems.

This subclass is indented under subclass 901. Subject matter wherein the information data to be switched
by the communication systems is organized with one or more bytes
preceded by an identification information indicative of a source
or destination station.

(2)Note. The structured layer approach allows partitioning complex
communication rules or protocols into independent functions which
could be individually modified or updated without destabilizing
the entire set of rules or protocols.

This subclass is indented under subclass 903. Subject matter wherein the network elements are interconnected
by counter rotating, dual ring fiber optic media wherein the communication
on the network is controlled used a token passing protocol.

This subclass is indented under subclass 903. Subject matter wherein the network is defined by a standard
which describes a point-to-point connection over a fiber optic network
which provides a digital communications hierarchy which resolves
incompatibilities between North America and European digital hierarchies
and is characterized by the STS-1 frame format which consists of
810 bytes.

This subclass is indented under subclass 908. Subject matter in which an idle or busy signal, indicative
of the status of the communications channel or path, is passed from
station to station on a closed transmission path.

This subclass is indented under subclass 908. Subject matter having a reservation scheme for reaching
a communication medium in which a station is assigned a carrier;
the idle state of a communication channel is determined by sensing
the presence or absence of a carrier signal on the channel.

Art collection of the multiplex communication system wherein
the information data to be communicated by the communication systems is
organized with one or more bytes preceded by an identification information
indicative of a source or destination station.

Art collection of the multiplex communication system having
plural nonmobile base stations providing service to different geos:graphical areas
which may overlap or may be contiguous, and wherein mobile stations
are in communication with the nonmobile stations by information
signals combined or distributed via separated time periods on a
transmission medium.

Art collection of the multiplex communication system including
methods or apparatus for formatting, converting, combining, or distributing
information signals for transmission or reception via more than
one time or frequency channel.

The definitions for FOR 100-FOR 196 below correspond to
the definitions for only the following abolished subclasses under
Class 370 from which these collections were formed: 53-57, 58.1-58.3,
59, 60, 60.1, 61-65, 65.5, 66-68, 68.1, 69.1, 70-84, 85.1, 85.11,
85.15, 85.2-85.9, 91-93, 94.1-94.3, 95.1-95.3, 97-99, 100.1, 101-103,
104.1, 105, 105.1-105.5, 106-109, 110.1-110.4, and 111-125. See
the Foreign Art Collection schedule for specific correspondences. [Note: The titles and definitions for indented art
collections include all the details of the one(s) that are hierarchically
superior.]

Foreign art collection including a switching device
used to reduce the number of transmission channels required to serve
remote stations by allocating a transmission channel to a remote
station only when the remote station requests service (e.g., by
going off hook).

Foreign art collection including subject matter
in which access to a transmission medium is divided into discrete
time intervals and information from respective channels is transmitted
in differing time intervals.

Foreign art collection including subject matter
in which the switching is organized to have only a time stage (which
reorganized the order of time slots) and a space stage (which switches
time slots on incoming lines to a desired outgoing line) in either order.

Foreign art collection including subject matter
in which the switching is organized to have first a time state (one
which reorganizes the order of the time slots) followed by a space
stage (which switches time slots on incoming lines to the desired
outgoing lines) followed by another time stage.

Foreign art collection including subject matter
in which the switching is organized to have first a space stage
(one which switches time slots on incoming lines to a desired outgoing
line) followed by a time stage (which reorganizes the order of the
time slots) followed by another space stage.

Foreign art collection including subject matter
in which an equivalent N-stage switch is achieved with less than
N-stages by "folding" back the output of one stage to connect with
the input of a preceding stage.

Foreign art collection including subject matter
in which information in time slots of incoming lines is switched
to desired destinations only by storing or delaying the information
until the desired instant of readout.

Foreign art collection including subject matter
in which time switching occurs by connecting the lines to be connected
to a common bus for a time sufficient to transfer information between
the lines (e.g., one time slot).

Foreign art collection including subject matter
in which the frequency spectrum of the transmission medium is divided
into segments and respective information channels are transmitted
in differing segments.

Foreign art collection including subject matter
in which devices that allow signals of certain frequencies to pass
are employed for signal combination or separation in a frequency
division multiplex system.

Foreign art collection including subject matter
in which access to the transmission medium is divided into discrete
time intervals, and information from respective channels is transmitted
in differing time intervals.

Foreign art collection including subject matter
in which packet information is combined with data for causing the
transmission and reception of time division multiplex information
to have proper time relationship.

Foreign art collection including subject matter
in which the network over which the packets are to be transmitted
consists of switching nodes, wherein the nodes are interconnected
to form a star-shaped, tree-shaped, or mesh-shaped network.

Foreign art collection including subject matter
having a reservation scheme for access to a communication media
in which any station is assigned a vacant time slot channel in a time
division multiplex frame on the media in response to that station"s
request for access and the assignment lasting until it is withdrawn.

Foreign art collection including subject matter
in which synchronization is achieved by identifying the absence
of data transmission for a predetermined interval (i.e., a gap)
and using that absence to identify a reference point within a transmission
interval.

Foreign art collection including subject matter
wherein synchronization of a pulse train is achieved by stuffing
extra pulses into the train when pulses arrive too slow or deleting pulses
from the train when pulses arrive too fast.

Foreign art collection including subject matter
wherein the clock frequency adjustment of one station is based upon
information about the status of clock signals originating at other
stations of the system.

Foreign art collection including subject matter
where information is read out at a faster rate than it is stored,
resulting in a time compression, or conversely where it is stored
at a faster rate than it is read out, resulting in a time expansion.

Foreign art collection including subject matter
with means for transmitting and/or detecting signalling
information ancillary to the principal information transmitted by
the system (e.g., dial pulse, on-hook/off-hook, and ringing
information all ancillary to the information conveyed by a telephone
call).

Foreign art collection including subject matter
in which gaps in the principal information transmitted are used
for the transmission of ancillary data, e.g., signalling data transmitted
during gaps in a speech signal.

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